1. Field of the Invention
The present invention relates to a camera having a function of correcting a shake, which detects an unintentional movement of hands in taking a picture, drives part of an optical system and corrects for said movement of the hands in order to prevent a blurred image.
2. Related Background Art
A typical apparatus used in a camera for correcting an unintentional movement of hands in taking a picture detects a shake of the camera caused by the movement of the hands by means of a shake detection device such as an angular velocity sensor availing itself of the Corioli's force, an acceleration sensor employing, for example, a piezoelectric element, or the like. An appropriate amount of correction is then calculated on the basis of the detected shake. A correcting lens is moved up and down as well as right and left according to the resultant appropriate amount of correction in order to correct an optical path.
As an actuator for driving the correcting lens, a voice coil, a motor, or the like is employed.
In such apparatus, the output from the shake detection sensor such as the angular velocity sensor or the velocity sensor which is used in the shake correction apparatus `drifts` (that is, varies with time) depending on the characteristics of the sensor itself and temperature. Thus, the output when velocity is 0 is not constant. Accordingly, it is difficult to judge whether the sensor stands still or not and to detect angular velocity or velocity with precision. And the `drift` of the output of the shake detection sensor becomes an error of correction.